A Novel Methicillin-Resistant Staphylococcus aureus t11469 and a Poultry Endemic Strain t002 (ST5) Are Present in Chicken in Ebonyi State, Nigeria

Background. The changing epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) from a hospital-associated pathogen to an organism commonly found in the community and in livestock reflects an organism well-equipped to survive in diverse environments and adjust to different environmental conditions including antimicrobial use. Methods. We investigated the molecular epidemiology of S. aureus and MRSA in poultry in Ebonyi State, Nigeria. Samples were collected from 1800 birds on 9 different farms within the state. Positive isolates were tested for antibiotic susceptibility and molecular typing. Results. Prevalence in birds was 13.7% (247/1800). MRSA prevalence in poultry was 0.8%. The prevalence of MRSA in broilers and layers was 1.2% and 0.4%, respectively. All tested isolates were susceptible to vancomycin. Molecular analysis of the isolates revealed 3 spa types: t002, t084, and a novel spa type, t11469. The novel spa type t11469 belonged to sequence type ST5. Conclusion. The detection of t002 in chicken suggests the presence of livestock-associated MRSA in poultry in Ebonyi State. The detection of the new spa type t11469 in poultry that has not been characterised to ascertain its pathogenic potential remains a cause for concern, especially as some were found to carry PVL genes, a putative virulence factor in staphylococcal infection.